Elastic bituminous spacing-plank for pavements.



C. N. FORREST.

ELASTIC BITUMINOUS SPACING PLANK FOR PAVEMENTS.

APPLICATION FILED JUNEG, 1913.

Patented Deo. 5, 1916.

Lmm

2 i: LES N. IIEORRES'I, OIF RAIIWAY, NEW JERSEY, ASSIGNOB. TO THE BARBER ASPHALT VIRGINIA.

PAVING COMPANY, OI' PHILADELPHIA, PENNSYLVANIA, A CORPORATION OIRWIEIIST JELASTIC JBITUMINOUS SPACING-ILANK FOR PAVEMEN'IS.

Specicaton of LettersUJPatent.

patented nee. a, taie.

G)Application filed J' une 6, 1913. Serial No. 772,039.

To all whom t may concern.'

Be it known that I, CHARLES N. FoRREsT,

of Rahway, in the county of Union and f;

State of New Jersey, have invented certain 5 new and useful Improvements .in Elastic Bituminous Spacing-Planks for Pavements, of which the following is a specification, reference being had to the accompanying draw- 1n s. l0 Idy invention relates to the productionof a spacing plank of elastic material, which is used as a substitute for and improvement upon the present method of constructing elastic spacing joints or filling blocks as used for the purpose of taking up the expansion and contraction of pavements,

My invention is particularly appllcable to block pavements and my spacing planks are designed for use in the same situation 2o and as substitutes for the elastic joints which have been heretofore provided.

In the accompanying drawings, Il`igure I, represents a spacing plank constructed according to my invention. lEig. II, is a view of a pavement showing the spacing planks in place.

Heretofore the practice in laying paving blocks, such as vitriiied brick or wood blocks, has been to place a wooden plank of suitable thickness and length adjacent to the curb on each side of the roadway, and to start and stop the various transverse courses of paving blocks from and ending at such planks, rather than from the curb line proper, or merely by leaving a longitudinal open space adjacent to the curblines. After a convenient area of blocks have been thus laid, the said strips of wood are removed and the open space from which they have been removed is illed with melted pitch or asphaltum. IIhe object of the lled space thus provided is to allow transverse movement ofthe paving blocks through expansion by heat or moisture, without dislocation of the curb line or buckling of the road way. I' have invented an improved plank for laying such block pavements which obviates the necessity of, first, the employment of the aforementioned wood 5o strips and the danger of disturbing the abutting blocks when that is removed, second, the necessity of melting pitch or asphaltum filler on the street and handling the same in a highly heated and dangerous condition.

Third, the waste of filling material by slopp1ng it about in a fluid condition, and fourth, the production of cleaner and more workmanlike piece of finished pavement.

It is obvious that the bituminous planks used .for this purpose must be elastic and ylelding in order to move in sympathy with the expansion and contraction of the pavement. Also notwithstanding their elasticity or plasticity, they must be sufiicientlyy cohesive and hard under all conditions of at. 65 mospheric temperatures to cause individual planks to retain their identity and shape, without sticking or flowing together, during transit from the point of manufacture to the f point of use. 'Ihey must also be suiciently 70 firm or cohesive to permit of convenient handling and placing. According to my invention7 spacing planks fulfilling these requirements are cast from a heated and melted material, in molds of suitable size, say one inch thick, three inches wide and six feet long, but obviously the-dimensions may vary to suit different types of pavement or different situations of use.

A suitable bituminous compound for the @Q planks is onev consisting of grahamite 21%, petroleum paradin residuum 49% and 30% of maltha. Such a combination of bituminous substances is characterized by a high y melting point,` (say over 190o notwith- .85

standing the softness or penetration of the combination, but it is possible by using other hard native bitumens in combination witli,` other bituminous materials to secure this* desired relationship between melting point 9o and penetration whereby there is secured a compound which is not hard or brittle at winter temperatures and which will not flow at summer temperatures and which at the same time does not present an excessively sticky surface. Previous efforts to attain this end have not produced the desired cmbination of qualities, and an envelop orcontainer has been required to render the material transportable. Such a plank is shown at 1, in lFig. I. If made in accordance with theabove directions it possesses the required qualities of elasticity, with some lasticit also of cohesiveness and non-ductility. j

Fig. II, I have indicated a portion of a block l pavement, showing such planks, 1, 1, inserted adjacent to the curb line 2, 2. Similar transverse spacing planlm 3, '3, are also to create an elastic joint in the pavement.

It will also be understood that the invention is not limited to a block pavement, nor to the recise dimensions specified.

aving thus described my invention, I claim: v

A transportable bituminous spacing plank, for use in the formation of joints of pavements comprising a `hard native bitumen, petroleum residuum and a heavy viscous bitumen, combined in such proportions as to produce a substance having moderate penetration, a melting point over 190 F. and that absence of stickiness upon its surface which renders the article capable of transportation and placing without any container.

In testimony whereof, I have hereunto signed my name at Maurer, N. J. this 27th day of May, 1913.

CHARLES N. FoRnEsT.

Witnesses:

M. A. BRAM, M. Y. GREENLAW. 

